Name ______Date ____ Class _____

Physical Geography of the United States and Canada

DiHerentiated Instruction

Tornado Alley A tornado is a violent, twisting column of air. It emerges from within a thundercloud and reaches down to the ground. Tornadoes can come in many shapes, but they usually form in the shape of a funnel. Some have wind speeds of up to 450 miles (724 km) per hour. Most tornadoes in the United States form in an area called "Tornado Alley." This area includes parts of several states, shown on the map below. Although tornadoes occur throughout the United States, especially along the Gulf Coast from Texas to Florida, people often think of the Great Plains when they hear about tornado activity. Tornado Alley Why do so many tornadoes form in Tornado Alley? The most destructive tornadoes originate from strong, rotating thunderstorms called supercells. The geography of the Great Plains is a perfect breeding ground for supercells. The land in this region is relatively flat. This allows cold, dry, polar air from Canada to meet warm, moist, tropical air from the Gulf of Mexico. Most tornadoes form 400 miles along the front-or meeting place-between these two air masses. Spring is the most active time for tornadoes. During this time of the year, tornadoes form mainly within Tornado Alley and east into the Ohio Valley. In summer, tornado activity moves mainly to an area extending from North and South Dakota into Pennsylvania and New York. Winter tornadoes usually form along the Gulf Coast. Tornadoes have been seen in alISO states.

Directions: On a separate sheet of paper, answer the following questions. 1. Identifying What is a supercell? 2. Theorizing Although tornadoes can form in any state, they rarely occur in the northeastern part of the United States. Why do you think this is so?

43 - Teaching Strategies for Different Learning Styles

The following activities are ways the basic lesson can be modified to accommodate students' different learning styles.

can they draw from the data? (Roughly 74% English Learners (EL) of all tornadoes are weak, 25% are strong, and 1 % Ask students to define the term Tornado are violent- but 67% of deaths come from violent Alley [the area of the United States where most storms.) tornadoes occur], and have them explain the Visual/Spatial significance of the shaded part of the map. [The shaded section denotes Tornado Alley.] Also Tornado Alley has no agreed-upon bound­ ask students if their community is located aries. The map accompanying the article is just within Tornado Alley. one representation. Ask students to find and map another version of Tornado Alley based Verbal/Linguistic; Intrapersonal upon different criteria. Display students' maps A storm chaser is a person who intention­ in the class. ally seeks out severe storms such as tornadoes. Advanced Learners Many storm chasers simply want to see the event, though some are scientists who follow The April 3-4, 1974, Super Outbreak was storms to conduct research. Storm chasing is the largest known outbreak of tornadoes in the particularly popular in the Great Plains. Ask United States, with 148 tornadoes forming in students to prepare a report about this activity. 11 states. Assign students to write a three-page report about this event. Visual/Spatial Verbal/Linguistic; Interpersonal Assign students to create tornado-themed art that depicts the power of the storm and Tornadoes have been prominently featured typical geographic features found in Tornado in a number of movies, stories, and songs. Alley. Divide the class into three groups, and have them use library or Internet resources to com­ Kinesthetic pile lists of as many of these as they can find. Directions for creating "homemade torna­ Share the lists in class to see who found the does" are easy to find online. Allow students most. to make a "tornado in a bottle" and demon­ Auditory/Musical strate it in class. Students should explain how their creations are similar to the storms that Invite students to compose a song that occur in Tornado Alley. either (1) explains how tornadoes form, or (2) explains the steps to take in the event of Logical/Mathematical a tornado. Allow students to perform their The Fujita Tornado Damage Scale is used compositions in class. to rate the intensity of a tornado. It examines the damage caused by a tornado after it has Below Grade Level passed over a human-made structure. Ask Ask students to use library or Internet students to create a table categorizing the resources to find the difference between a different levels of the scale. Also ask them tornado watch and a tornado warning. Have to create two circle graphs: one showing the them explain the difference in a paragraph. percentage of all tornadoes since 1960 (or some other specific period) that were weak (FO-Fl), strong (F2-F3), or violent (F4-FS); and one showing the percentage of deaths caused by these levels of tornadoes. What conclusions

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